Chain lock



Oct. 12, 1948. LECQMPTE 2,451,100

' CHAIN LOCK' Filed Aug. 30, 1946 1' I 5 lbw/#01 I flimalzdlewmpfe Patented Oct. 12, 1948 UNITED STATES PATENT OFFICE CHAIN LOCK Armand Lecompte, Montreal, Quebec, Canada Application August 30, 1946, Serial No. 693,913

- In Canada September 6, 1945 l-Claim. l

The present invention pertains to a novel chain lock to prevent the theft of various articles such as bicycles in particular.

The principal object of the invention is toprovide a device of this character wherein the chain is automatically drawn in when not in use in order not to interfere with the movements of the cyclist. Another object of the invention is to provide such a device that can be conveniently mounted on the frame of a bicycle and does not detract from the appearance thereof.

Still another object of the invention is to provide a device of this character wherein the chain is easily withdrawn from a housing carried by the bicycle by the unwinding of a cylinder or drum within the housing. A further object is to provide such a device wherein the chain may automatically be wound up in the housing when not in use.

In the accomplishment of these objects, the device comprises an elongated housing adapted to be secured to the frame of the bicycle and in which is rotatably mounted a cylinder. The cylinder is preferably formed with an external screw thread shaped in such a manner as to wind a chain thereon. One end of the chain is fixed to the cylinder, and the other end passes through a longitudinal slot in the housing. The free or external end of the chain preferably carries a padlock adapted to be fastened to a suitable bolt carried by the housing.

The invention further includes a coil spring mounted within the drum in a manner to be tensioned as the chain is withdrawn. A ratchet mechanism associated with the drum holds the latter in its tensioned condition. The ratchet is provided with a pawl adapted to be released manually by a fingerpiece exposed externally of the housing. When the chain has been unlocked, the ratchet is released in the manner described, and the spring rotates the cylinder to wind the chain on the latter.

The invention is fully disclosed by way of eX- ample in the following description and in the accompanying drawings in which:

Figure l is a longitudinal section of the device;

Figure 2 is a section on the line 2-2 of Figure Figure 3 is a perspective view illustrating the device in use; and

Figure 4 is a detail cross section showing the ratchet mechanism.

Reference to these views will now be made by 2 7 use of like characters which are employed to designate corresponding parts throughout.

The mechanism of the device is enclosed in a cylindrical housing Ipreferably made of metal and closed at its ends by disks 2 and conical cap-s 3. The disks are apertured at the center to receive the reduced ends of a shaft l. The ends of the shaft are extended into the caps 3, and one of the extended ends carries a lever 5 and the other a flanged sleeve 6, passing through the adjacent disk 2, with the flange 8 within the housing I supporting one end of a co-axial cylindrical tube 9 spaced from the inner wall of the cylinder I. The other end of the tube 9 is supported on a disk 8' carried by the shaft 4 at the inner side of the adjacent disk 2.

The outer surface of the tube 9 is formed with a spiral thread ID extending into close proximity of the inner wall of the housing I and spaced sufiiciently therefrom to permit rotation. The spaces between the convolutions of the thread are sufficient to accommodate a chain, as will presently appear. The locking chain I I is wound on the tube 9 and extends between the convolutions of the chain as may be seen in Figure 1. One end of the chain is fastened to an end of the tube 9 by a screw I2. A longitudinal slot I3 formed in the housing I slidably receives a guide ring I4 through which the chain I I extends to the bicycle or other object to be locked. The guide ring is itself guided by adjacent convolutions of the thread III which fit into it, as shown in Figure 1.

The ratchet wheel I is engaged by an angular pawl I4 pivoted at I5 to the inner surface of the adjacent cap 3. A finger I5 is slidably mounted through the cap and engages the non-locking arm of the pawl so that the locking arm may be disengaged from the pawl at will.

The housing I is normally fixed to the frame I6 of a bicycle I! by a tubular clip I8 enclosing the horizontal bar of the frame. The free end of the chain carries a small padlock I9. The cap 3 that contains the lever 5 is formed with a hole 20 that provides access to a bolt 2| to which the padlock I9 is adapted to be locked.

In the use of the device, when it is desired to chain the bicycle to a fixed member such as a post 22, the chain is pulled out of the housing I suffrciently to encircle the post as shown in Figure 3. The lock I9 is then engaged with the bolt 2|, if absolute locking is desired. It is apparent that the chain may be passed around the bicycle frame and the post 22 in various ways. In order to protect the bicycle frame from being marred by the chain, the frame is fitted with a small stirrup 23 through which the chain is adapted to pass, as also shown in Figure 3.

The cylinder 9 contains a coil spring 24 having one end secured to the disk 8 by a screw 25 and the other end to the shaft 4 by means of a sleeve 26 secured on the shaft by a screw 21. The lever 5 engages screw 28, whereby the shaft 4 is prevented from rotating. The spring is wound as the chain H is pulled out and is maintained in tensioned condition by the engagement of the pawl M with the ratchet I. When it is desired to draw in the chain on releasing it from the member 22, the pawl is disengaged from the ratchet by pushing on the finger l5, whereupon the tensioned spring turns, the cylinder '9 and causes the chain to be wound on'the cylinder.

housing having a longitudinal slot, a guide sl'idarble in said slot, a chain passing through said guide and having one end fixed to said cylinder, said cylinder having a thread receiving said chain, said thread having successive convolutions fitted into said guide, a coil spring in said cylinder, said spring having one end fixed to said cylinder and the other end fixed relatively to said housing, a ratchet onsaid cylinder, and a pawl in said hous ing and engaging said ratchet.

ARMAND LECOMPTE...

REFERENCES CITED The following references are of record in the Although a specific embodiment ottheinvenfile of this patent:

UNITED STATES PATENTS Number Name Date 807,965 Rice Dec. 19, 1905 972,741 Wedell Oct. 11, 1910 7 1,520,808 Chippindale Dec. 30, 1924 FOREIGN PATENTS I Number Country Date 7 802,885 France June 22, 1936 

